1. Field of the Invention
The invention relates to a supporting frame, more particularly to a supporting frame for mounting a seat device on a bicycle seat post.
2. Description of the Related Art
Referring to FIG. 1, a conventional seat assembly 1 for a bicycle includes a seat device 11, a supporting frame 12, a seat post 13, and a clamp unit 14. The supporting frame 12 is connected to a bottom face 111 of the seat device 11 through a three-point supporting method, and includes two supporting arms 121. The seat post 13 has a seat-mounting member 131 formed on a top end thereof. The clamp unit 14 includes a lower clamping member 141, and an upper clamping member 142. The lower clamping member 141 is superimposed on the seat-mounting member 131, and cooperates with the upper clamping member 142 to clamp therebetween the supporting arms 121 of the supporting frame 12. A threaded bolt 143 is passed through the seat-mounting member 131 and the lower and upper clamping members 141, 142, and engages an engaging piece 144 so that the supporting frame 12 is clamped securely between the upper and lower clamping members 142, 141.
Although the aforementioned conventional seat assembly 1 can achieve its intended purpose, it has the following drawbacks:                1. The supporting frame 12 is connected to the seat post 13 through the upper and lower clamping members 142, 141. This configuration as such results in the conventional seat assembly 1 having many components so that assembly of the same is complicated.        
2. The upper and lower clamping members 142, 141 cannot stably clamp the supporting frame 12 because of gaps that are formed between the upper and lower clamping members 142, 141 when the clamping members 142, 141 are coupled. This results in unsteady support of the seat device 11.